12AX7 substitutions

[W2JBL]

are the ribs on that 12AX7 plate the infamous "pleasure ribs" as used on certain condoms? let's get real here boys and girls. this guy is talking about a  DX60, not the space shuttle. high school tube swapping is allowed on a DX60. my personal DX60 has a 12AU7 in the speech amp, because it's what I had for a spare 300 miles from nowhere when the 12AX7 died. I get really smooth audio with a nice "brown tone" from that rig.